Method and apparatus for sealing a pipe line



Dec. 7, 1965 L. H. MORSE 3,221,758

METHOD AND APPARATUS FOR SEALING A PIPE LINE Filed March 22, 1962 2Sheets-Sheet 1 ill!!! luveziioa' L m H. Mar sa,

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flii'oflney Dec. 7, 1965 L. H. MORSE 3,221,758

METHOD AND APPARATUS FOR SEALING A PIPE LINE Filed March 22, 1962 2Sheets-Sheet 2 ///'l ///I//// l 132194322302 Lyem H.Mor se,

United States Patent 3,221,758 METHOD AND APPARATUS FOR SEALING A PIPELINE Lynn H. Morse, Venice, Fla, assignor to (Bruce Iuc., Worcester,Mass, a corporation of Massachusetts Filed Mar. 22, 1962, Ser. No.181,668 8 Claims. (Cl. 13715) This invention relates to the repair orreplacement of existing pipe lines which require renewal because ofleakage, aging, or other reasons.

A common problem of renewing the buried iron supply pipe line whichdelivers natural or manufactured gas from the public utility companysmains under the street to the building or house where it is consumed, isfrequently solved in practical manner by running a continuous length ofsoft copper tubing or of plastic tubing through the existing iron supplypipe from a point adjacent the gas meter in the building clear to themain in the street. This saves the heavy cost and delay of digging upthe old pipe line, removing and replacing it, and reburying it. All thatremains to be done is to connect one end of the copper or plastic tubingto the main after cutting off a short length of the iron pipe to giveroom for the connection, and joining the other end of the tubing to themeter connection.

Requirements of safety dictate that the entire gas line within thebuilding from the point of entry to the meter be composed of rigid ironpipe, and so the joining of the tubing to the meter connection must bemade within the .iron pipe or the iron fittings thereon. Various wayshave been proposed for sealing the delivery end of the tubing to theinterior of the iron pipe or fittings. Such provision is necessary toprevent back-flow of gas through the space between the interior wall ofthe old iron pipe and the exterior of the tubing within it, witheventual escape at the cut-off end of the iron pipe adjacent but shortof the main, or at leaks in between the building and the main orelsewhere. But all with Which I am acquainted have been so cumbrous orso relatively expensive as to leave room for improvement.

The present invention thus aims to provide a means of sealing theflexible tubing to the rigid iron pipe, and a method and apparatus forapplying and installing such means, that will be cheaper, easier, andquicker to install, safer, and practically proof against failure.

To these ends, the invention basically lies in a novel composite sealcomprising a metal taper collar to be wedged into the indoor end of theiron supply pipe and fixed compressively about the tubing, an annularpreferably non-metallic elastic radially-expansible packing ring bearingagainst the collar and the iron pipe and the tubing, and a springcontinuously pressing the packing ring against the metal collar andexpanding this ring radially outward against the iron pipes interiorwall and radially inward against the outside wall of the tubing.

Further features of the invention are the method and apparatus providedto prepare for and install the parts of the novel seal. Thus, thecast-iron T initially present, or one installed, on the building end ofthe iron supply pipe where it emerges from the foundation and the lineturns to the meter or regulator, is used as the body and anchorage of ajig for successively reaming the old supply pipe end and thereafterseating the taper collar in sealing position.

An additional feature of the invention is the facility it offers for theinstallation of a heat-responsive automatic gas shut-off, called a firevalve for short. The spring which loads the elastic packing ring is of'helical expanding type, mounted coaxially with the tubing on the end ofthe latter, and thus can be and is used as a guide for a cylindricalaxially expandible cell having a valve Patented Dec. 7, 1955 ice memberon its end to seat upon and close the adjacent end of the tubing in caseof fire near the meter and the entry point of the supply line.

Other objects of the invention, and the manner of their attainment, areas set forth hereinafter.

An illustrative embodiment of the invention is shown in the accompanyingdrawings, in which FIG. 1 shows a portion of the delivery end of an irongas supply pipe and a T applied thereto, with the tubing sealed in placeby the novel seal, all parts being shown in vertical axial section.

FIG. 2 shows mainly in side elevation a reamer to be inserted in the Tand used for preparing a seat in the iron pipes end for the tapercollar, the cutting flutes being omitted.

FIG. 3 shows mainly in side elevation a tool to be inserted in the T toseat the metal taper collar in the iron pipe and about the tubing,

FIG. 4 is a side elevation of the metal taper collar.

FIG. 5 is a view similar to FIG. 1 showing the fire valve in place, anda reinforcing sleeve used inside the tubing when the latter is ofplastic.

In the drawings, the iron supply pipe is indicated at 1, with the usualcast-iron T 3 screwed onto its delivery end within the building. The hub5 receives the pipe which con-ducts the gas to the meter or reducingvalve. The hub 7 in line with pipe 1 is conventionally closed by acommon pipe plug (not shown), and serves to admit cleaning implements.It also serves to permit the introduction of the continuous length ofsoft copper or plastic tubing 9 or 10, of sufficiently less outsidediameter than the internal diameter of the iron pipe 1 to enable it tobe drawn through pipe 1 for the latters full length by a steel wire orelectricians snake.

In accordance with the invention, in preparation for the insertion ofthe tubing 9 into the iron pipe 1, the cleanout plug is removed from hub7 and replaced by the screw-threaded and hexagon-headed plug 15, FIG. 2,through which extends the round shank 17 of a reamer 19 having acylindrical portion 21 at mid-length which is approximately .030 inchlarger than the standard internal diameter of the particular iron pipe 1in use, another zone 23 nearer its end having a 5 or more straighttaper, and a third zone 25 farther from its end and having a straighttaper of from 15 to 30, the portion 27 of maximum diameter beingsubstantially .100" greater than the standard internal diameter of thepipe 1. Upon insertion of this reamer into the end of pipe 1 androtation by suitable means applied to its shank 17 outside the guideplug 15, a taper seat 29 having zones complementary to the describedzones of the reamer is formed in the end of the iron pipe. The reamercuts deeply enough to eliminate all rust, pits, and scale otherwisepresent in the corresponding end portion of the pipe. After reaming theseat 29 in the end of the iron pipe to a smooth surface, the reamer andits guide plug 15 are removed, and the flexible tubing 9 is drawnthrough the old pipe 1 until it reaches the main in the street,whereupon the tubing is severed smoothly as indicated at 11 while stilloutside the T 3, and then the tubing is drawn forward until its end 11is located A" or so out from the end of iron pipe 1, as shown.

Next, in accordance with the invention, an annular member in the form ofa collar 13, FIGS. 1, 4 and 5, of relatively soft and deformable metal,preferably brass, having a cylindrical interior bore of sufiicientlygreater diameter than the outside diameter of the tubing to slide overit easily, and preferably an exterior which is part cylindrical and parttaper (about half and half) is fitted over the end of tubing 9 andpress-fitted into seat 29 of the pipe 1, being wedged thereinto sotightly as to contract upon and compressibly grip the tubing 9 itencircles. When plastic tubing is used, a metal reinforcing sleeve 30with a terminal flange is slipped inside the tubing to support itagainst the inward pressure of collar 13, as shown in FIG. 5. Thecylindrical portion of the taper collar 13 exceeds the diameter of thecylindrical portion, the mid-section, of seats 29 in pipe 1 by .010" to.015", the tapered inward end portion of l the collar having a diameterof approximately .040 less than the cylindrical portion. While thesedimensions of reamer and collar are adapted for use in inserting anominally A ID. tubing in the conventional I.D. iron pipe, they areillustrative only, the basic principle being that the taper collar is ofthe proper dimensions and ductility to be swaged by the seat formed inthe iron pipe acting as a die, and thus compressed radially like a glandinto tight gripping relation about the tubing 9. The taper collar isaccordingly provided with a plurality of peripheral grooves 31 toprovide voids into which the metal of the collar can flow under thedistortion incident to swaging and wedging it into its seat 29 in pipe1.

The invention provides the means for applying the heavy pressure desiredand needed to swage the taper collar 13 .thus into place, by supplying atool, FIG. 3, which converts the T 3 into a screw-press which seats thecollar 13 in the manner desired. This tool comprises a cup-shapedpresser 41 whose recess 43 fits easily over the end of the tubing 9 andwhose rim 45 is adapted to engage the big end of collar 13 after thelatter has been installed on the tubing 9 and in the flaring outer-.most portion 57 of seat 29, as by using long-nosed pliers or othermeans. The presser .41 is mounted rotatably on the end 46 of ascrew-threaded shaft or shank 47 which is threaded through a guide plug49 with hexagonal head .50 which is screwed in the hub 7 of the T 3temporarily while the tool is in use. The head 51 of shank 47 isprovided with a transverse hole 53 in which a bar may be inserted torotate the screw shank 47 and thus impel the presser 41 against tapercollar 13 with the force required to swage the latter into place. Thetool is thereupon removed.

The collar 13 installed in the iron pipe 1 thus functions as amechanically tight seal connecting and centering the iron pipe and thetubing, and may or may not be in gas-tight relation. But its mainpurpose is to provide a seat or stop against which to press a secondannular member in the form of a non-metallic elastic packing ring 55which underaxial pressure is expandible both radially inward andradially outward, and comprises the actual essential gas-tight seal.Herein, this packing ring is made of neoprene, preferably having a taperroughly matching the slope of the reamed taper 57 at the mouth of theseat formed in the end of pipe 1. This ring is slid over the end oftubing 9 or 10, followed by one or more metallic washers 59 slightlyless than the diameter of the hub 61 into which the iron pipe 1 isscrewed. Then a stiff expanding coil spring 63, fitting closely on theoutside of tubing 9 or 10, is placed over the end of tubing 9 or 10 tobear against the washer 59.

The pressure of spring 63 when stressed, and delivered to the ring 55through the washer 59, is of such intensity as to compress the ring 55axially and thus expand it radially into gas-tight sealing relation tothe outer wall of tubing 9 or 10 and the inner wall of pipe 1,specifically at the bevel 57 therein.

To load the spring, a special plug .65, permanently replacing theoriginal clean-out plug, now discarded, is provided and installed in thehub 7. This plug has a coaxial boss 67 which enters and centers thespring 63 in axial alignment with the pipe 1 and tubing 9 or 10, whilethe adjacent annular shoulder or inward face 69 of plug 65 compressesthe spring and causes it to load the washer 59 and thus press and holdthe neoprene packing ring 55 permanently in gas-tight sealing relationwith the tubing 9 and the pipe 1. A suitable polygonal socket 71 isformed in the outer end of the plug 65 for the reception of acorrespondingly shaped wrench whereby to insert and remove the plug.Where still greater pressure on packing ring 55 is needed, or otheradjustment of the spring tension is wanted, additional steel washers 59are interposed between the ring and the spring.

Preferably this socket 71 and matching wrench will have an odd number orshape of facets, to reduce the possibility of unauthorized removal ofthe plug. To the same end, the socket is preferably counterbored asshown at 73 for the reception of a press-fitted sheet-metal seal 75 withor without identifying insignia of the public utility company.

The spring 63 being of open wind opposes no obstacle to the free flow ofgas from tubing 9 or 10 through the T to the pipe (not shown) applied tohub 5 and leading to the meter or regulator.

The economy of the present invention will be obvious, as it involves noreplacement of pipe or fittings or openings of joints in the originalpipe line, even in the ,case of the smallest supply pipe sizes ,used instandard installations. Beyond the substitution of the special plug 65,of essentially inexpensive construction, all that is needed to completethe structure are the three simple annular components 13, 55 and 59, andthe spring .63. Once the reaming of iron pipe 1 and the installation ofthe flexible tubing 9 or 10 are completed, it is only a matter of a fewminutes work to install the improved seal in permanent working relation.

The construction facilitates the installations of a heatresponsiveautomatic shut-off or fire valve, as shown in FIG. 5. An improved formof the latter comprises a cell made of two telescoped cups 79, 81,sweated together by low-temperature fusible metal having a melting pointin the range between 165 and 250 R, which hold under compression a coilspring 83 initially several times their length. A washer 85 of diameterequal to that of tubing 9 or 10 and of suitable flexible, gasimpervious,and heat-resisting material such as Neobestos, overlain by a smallermetal washer 87, is afiixed to the end of the cell adjacent the tubing,9 by a rivet 89. This fire valve fits loosely and slidably within theheavy coil springs 63, which thus also performs the function of guidingthe cup 79 accurately toward the end 11 of tubing 9 or of the sleeve 30until the valve material 85 is seated correctly and tightly against andclosing the tubing, when the fusible metal lets go under its rise intemperature in case of fire.

While I have illustrated and described a certain form in which theinvention may be embodied, I am aware that many modifications may bemade therein by any person skilled in the art, without departing fromthe scope of the invention as expressed in the claims. Therefore, I donot wish to be limited to the particular form shown, or to the detailsof construction thereof, but

What I do claim is:

1. Sealing means for a pipe line having in combination a relativelyrigid pipe having a tapered seat in one end, a relatively flexible pipewithin the rigid pipe and at least coextensive therewith, a deformablemetallic collar compressively surrounding the flexible pipe and having atapered exterior surface wedged in the seat, and a nonmetallic packingring between the inner and outer pipes and in gas-tight relation withthe two pipes and the collar.

2. The combination according to claim 1 in which resilient means isprovided ever pressing the packing ring inward into the rigid pipe.

3. Sealing means for a pipe a relatively rigid pipe, a T on an endthereof, a relatively flexible pipe within the rigid pipe, a deformablemetallic collar wedged inside the end portion of the rigid pipe andgripping the flexible pipe, a non-metallic packing ring wedged in therigid pipe and bearing against the flexible line having in combinationpipe, a helical spring within the T and pressing the packing ringagainst the collar, and screw means in the T loading the spring.

4. Sealing means for a pipe line having in combination a T, a relativelyrigid pipe fixed in one end of the T, a relatively flexible pipeextending throughout the rigid pipe and having one end within the T, adeformable metallic collar wedged into the fixed end of the rigid pipeand compressively gripping and surrounding the flexible pipe, anon-metallic radially expansible packing ring in the mouth of the rigidpipe, a helical spring encircling the end of the flexible pipe withinthe T and pressing the packing ring into sealing contact with the collar:and the two pipes, and a plug in the T in line with the pipes andloading the spring.

5. Sealing means for a pipe line having in combination a T having twocoaxial hubs, a pipe having one end fixed in one hub, a plug in theother hub, a coil spring in coaxial relation wi-th the pipe and locatedbetween the pipe and the plug, a cylindrical axially expandibleheat-responsive element coaxially and slidably disposed in the coilspring and movable independently of the latter, and closure means forthe pipe on the end of the element confronting the end of the pipe.

6. Sealing means for a pipe line having in combination a rigid metallicpipe, a plastic pipe within the rigid pipe and at least coextensivetherewith, a rigid metallic sleeve within the plastic pipe, a metalliccollar around the plastic pipe and wedged in the rigid pipe andcompressing the plastic pipe against the sleeve therein, and anon-metallic packing ring wedged between the two pipes and seated on themetallic collar and in gas-tight contact with the two pipes and thecollar.

7. The method of sealing a pipe line composed of a T, a pipe having oneend screwed into the T, and a second pipe within the first pipe, whichmethod comprises forming a taper seat in the end of the outer pipe,inserting the second pipe into the outer pipe, placing a collar aroundthe end portion of the inner pipe and within the taper seat, swaging anddeforming the collar into wedging relation with both pipes by pressuremeans reacting against the T, thereafter placing a flexible packing ringabout the end portion of the inner pipe and within the taper seat, andholding the packing ring pressed against the collar and the adjacentsurfaces of the tWo pipes by pressure means confined within and reactingagainst the T.

8. The method of sealing a pipe line which includes a rigid pipe, a T onthe end of such pipe having hubs in line with the pipe, and la flexiblepipe Within the rigid pipe and the T, comprising the steps of using onehub of the T as a guide for a tool used to form a seat in the rigidpipe, then using the hub as an abutment in press-fitting a stop memberin the seat in the rigid pipe, and thereafter using the hub as anabutment to load spring means holding a packing element against thestop.

References Cited by the Examiner UNITED STATES PATENTS 245,056 8/ 1881Callahan 29237 389,441 9/1888 Callahan 29-237 610,359 9/1898 Lees 285375770,525 9/1904 Hussey 285177 800,740 10/ 1905 Hoelder 13775 912,2332/1909 Dismuth 285-375 998,884 7/1911 Elvin 28591 1,299,934 4/1919Harnett 285339 1,304,126 5/1919 Venable 285343 1,574,017 2/1926 Beattie251-214 2,131,094 9/1938 Clark 13779 2,397,290 3/1946 Rasmussen 2853422,470,546 5/ 1949 Carlson 285-3827 2,487,939 11/1949 Norton 285-1382,529,821 11/1950 Snider 285334.1 2,641,491 6/1953 Mueller et al.285-138 ISADOR WEIL, Primary Examiner.

CARL W. TOMLIN, THOMAS F. CALLAGHAN,

Examine

5. SEALING MEANS FOR A PIPE LINE HAVING IN COMBINATION A T HAVING TWO COAXIAL HUBS, A PIPE HAVING ONE END FIXED IN ONE HUB, A PLUG IN THE OTHER HUB, A COIL SPRING IN COAXIAL RELATION WITH THE PIPE AND LOCATED BETWEEN THE PIPE AND THE PLUG, A CYLINDRICALLY AXIALLY EXPANDIBLE HEAT-RESPONSIVE ELEMENT COAXIALLY AND SLIDABLY DISPOSED IN THE COIL SPRING AND MOVABLE INDEPENDENTLY OF THE LATTER, AND CLOSURE MEANS FOR THE PIPE ON THE END OF THE ELEMENT CONFRONTING THE END OF THE PIPE. 